In image analysis, it is important to detect the lines which represent the edges of the objects in the image. The most popular technique to detect the lines is Hough Transform. In the transform, resulting peaks in the accumulator array which are gotten by a voting procedure in the parameter space represent strong evidence that a corresponding line exists in the image. In the voting procedure, a large number of votes which are far from the peaks are unnecessary and it makes the transform slow. In this article, we propose a speed-up method by introducing a procedure (using a inter-image operation) in image space which removes lines except for limited directional lines. Owing to the procedure, we can reduce voting range and remove the unnecessary vote. From the experimental results, we confirm that the proposed method has good performance.%画像中から直線を抽出することば物体認識を行う上で非常に重要な問題であり，中でも代表的な手法としてHough変換が知られている.しかし，Hough変換は直線として抽出されるパラメータ値から大きく離れたパラメータ値への冗長な投票が多く，処理時間に影響を与えてしまう．本稿では，画像空間における簡単な処理を用いることで，この冗長な投票を削減する手法を提案する．また，本手法が十分な精度を保ったまま高速化を実現するものであることを実験により確かめる．
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